The mission of the Molecular Biology/Molecular Genetics (MBMG) Core is to assist investigators seeking to discover the molecular bases of obesity and its co-morbidities. Through collaborative efforts with other NYONRC Cores, the effects of defined genetic alterations in humans and rodents on ingestive behavior, energy balance, body composition, and endocrine function can be characterized. The role of candidate molecules in tissues and cells related to energy homeostasis can be delineated through experimentation on both human subjects and rodent models. Access to sophisticated manipulations of the mouse genome and to in vitro manipulation of genes are also critical to generating and testing hypotheses with regard to mechanisms by which genetic effects are conveyed. Finally, the use of stem cells to replicate the cell-based consequences of genetic variation is playing a rapidly growing role in biomedical research. The modern tools of molecular biology and molecular genetic analysis comprise rapidly expanding techniques for acquiring and interpreting large amounts of data relating to gene sequence, variation in genomic architecture, gene expression and gene function. These approaches require specialized, costly equipment, skilled technical personnel and increasingly intense and complex computational analysis, all of which are inefficiently replicated in multiple individual laboratories. The objectives of the MBMG Core are to minimize barriers to the integration of cutting edge technologies of molecular genetics and genomics into the research of the Center's constituencies;to allow experienced investigators as well as researchers who are not molecular geneticists to add this dimension to their studies at reasonable cost.